Melatonin

Written by HealthyPlace.com Staff Writer

Page 1 of 5

Comprehensive information on melatonin supplements for depression, seasonal effective disorder (SAD), insomnia and eating disorders. Learn about the usage, dosage, side-effects of melatonin.

Overview

Melatonin is secreted by the pineal gland in the brain and is important in the regulation of many hormones in the body. Among its key roles, melatonin controls the body's circadian rhythm, an internal 24-hour time-keeping system that plays an important role in when we fall asleep and when we wake up. Darkness stimulates the release of melatonin and light suppresses its activity. Normal melatonin cycles are disrupted when we are exposed to excessive light in the evening or too little light during the daytime. For example, jet lag, shift work, and poor vision can disrupt melatonin cycles. In addition, some experts claim that exposure to low-frequency electromagnetic fields (as is common in household appliances) may disrupt normal cycles and production of melatonin.

Melatonin is also one of the hormones that controls the timing and release of female reproductive hormones. As a result, melatonin helps determine when menstruation begins, the frequency and duration of menstrual cycles, and when menstruation ends (menopause). Many researchers also believe that levels of melatonin in the body are related to the aging process. For example, young children have the highest levels of nighttime melatonin and these levels are thought to diminish progressively with age. This decline likely contributes to why many older adults suffer from disrupted sleep patterns and tend to go to bed earlier and wake up earlier in the morning than when they were younger. However, emerging research is bringing the idea of diminished melatonin levels in the elderly into some question. Therefore, those considering use of this supplement should first talk to their healthcare provider about having blood levels of melatonin checked.

In addition to its hormone actions, melatonin also has strong antioxidant properties and preliminary evidence suggests that it may help strengthen the immune system. Because melatonin is a potent hormone, it's advisable to check with a healthcare provider before using it as an antioxidant supplement.

Uses

Melatonin for Insomnia
Although results are still controversial, studies suggest that melatonin supplements help induce sleep in people with disrupted circadian rhythms (such as those suffering from jet lag or poor vision or those who work the night shift) and those with low melatonin levels (such as some elderly and individuals with schizophrenia). In fact, a recent review of scientific studies found that melatonin supplements help prevent jet lag, particularly in people who cross five or more time zones.

A few studies suggest that when taken for short periods of time (days to weeks) melatonin is significantly more effective than placebo in decreasing the amount of time required to fall asleep, increasing the number of sleeping hours, and boosting daytime alertness. In addition, at least one study suggests that melatonin may improve the quality of life in people who suffer from insomnia and some experts suggest that melatonin may be of value for children with learning disabilities who suffer from insomnia.

Although research suggests that melatonin may be modestly effective for treating certain types of insomnia as described, few studies have investigated whether melatonin supplements are safe and effective over the long term.

Osteoporosis
Melatonin has been shown in laboratory studies to stimulate cells called osteoblasts that promote bone growth. Given that melatonin levels may also be lower in some older individuals such as postmenopausal women, current studies are investigating whether or not decreased melatonin levels contribute to the development of osteoporosis, and whether treatment with melatonin can help prevent this condition.

Menopause
Melatonin supplements may benefit menopausal women by promoting and sustaining sleep. Peri- or postmenopausal women who use melatonin supplements to regulate sleep patterns should do so only for a short period of time since long term effects, as indicated earlier, are not known.

Melatonin for depression (Melotonin for SAD)
In one small study of 10 people with a particular type of depression known as seasonal affective disorder (depressive symptoms that develop during the winter months when exposure to light is lessened), those who received melatonin supplements had significant improvement in their symptoms compared to those who received placebo. Given the small size of this study, however, more research is needed before conclusions can be drawn regarding use of melatonin for either seasonal affective disorder or any other type of depression. This is particularly true since one study from the 1970s suggested that symptoms of depression may worsen when taking melatonin.